Steam-pressure gage



(No Model.)

G.H.OROSBY.. STEAM PRESSURBGAGB. No. 272,860. Patented Feb. 27,1883.

N. PEYERS. M Wilma. D, C.

UNITED STATES i ATENT OFFICE.

GEORGE H. CROSBY, OF SOMERVILLF, MASSACHUSETTS.

STEAM-PRESSURE GAGE.

SPECIFICATION forming part of Letters Patent No. 272,860, dated February 2'7, 1883.

Application filed December 11, 1882. (No model.)

To all whom it may concern Be it known that I, GEORGE HANNIBAL CROSBY, of Somerville, in the county of Middlesex, of the Commonwealth of Massachusetts, have invented a new and useful Improvement in Steam-Pressure Gages; and I do hereby declare the same to be described in the following specification and represented in the accompanying drawings,-of which- Figure 1 is a front view, and Fig. 2 a vertical and transverse section, of a pressu regage containing my improvement, the cover and dial of the case being removed in order to show the Bourdon expansion-tube.

In carrying out my improvement I provide the case and its expansion-tube with a chamber arranged in the case or in or at its back, and opening at or near its bottom into'the tube at its lower part, and provided at top with an induct and at bottom with an educt and a waste-water cook or valve, all being substantially as set forth.

In the drawings, A denotes the case of a steam-pressure gage, and B the Bourdon expansion-tube, arranged in such case in manner as shown, the tube at its middle or lower part communicating with or opening into the water-chamber C, which, in this instance, is

shown as at or in the back of the case, and extending from the lower to the upper part thereof, or to a height above that of the expansion-tube. This chamber at its upper part is provided with an induct, a, and at its lower part with an educt, b, having adapted to it a discharge-cook, c. When the gage is in use the induct a is to communicate with the steam boiler or generator in such manner or by such means as to enable steam therefrom to flow into the chamber, and from thence into the expansible-tube, and to condense in both, so as to charge them with water. The water-cock is to discharge such water when in cold or freezing weather the gage may not be in use and there may be a liability of the water freezing in either the expansible tube or in the chamber, and by so doing bursting or otherwise injuring the tube or chamber.

It is to be understood that the inductionpipe for the conveyance of the steam to the chamber should or may be provided with a stop-cock to cut off the flow of steam thereto as occasion may require.

The water-chamber, arranged with the expansion-tube in manner as represented, serves to keep the-latter charged with water, it not being desirable for the steam to enter the upon its back, or be applied thereto as may be most convenient.

In the drawings the chamber is represented as having its walls an integral part or parts of the case, or in one piece therewith. The mechanism connected with the expansible tu bc, and for operating, by the contraction and expansion of it, the index-pointer of the gage, is shown in Fig. 1, but need not be described, as it is such as is in common use in the wellknown Crosby steam-gage.

By my improvement the cxpansible tube is made to constitute part of a water-trap to prevent the steam from entering such tube, such improvement rendering the water not liable to boil out of the trap, as is the case where an ordinary trap is used, and the tube constituting no part of it. My improvement renders the gage pro-eminently useful for locomotive or portable steam-boilers.

Y Vhat I claim in a steam-pressure gage is as follows, viz:

1. The water-chamber situated in the gagecase, or in or at its back, and provided with an induct, in combination with the Bourdou expansible tube of such gage in communication therewith, substantially as set forth.

2. The water-chamber situated in the gagecase, or in or at its back, and provided with an inductand an eduction cock, in combination with the Bourdon expansible tube ofsuch gage, and communicating therewith, substantially as set forth. 4

GEORGE HANNIBAL CROSBY.

Witnesses: 1

R. H. EDDY, S. N. PIPER. 

